article: Rent a room
  Spare room? Not only will a lodger   earn you some money, but also, thanks to the government-backed "rent a room" program, you won't have to pay any tax   on the first PS4,500 you make per year. Try advertising your room on Roomspare or Roommateeasy.
  Make money during special events
  Don't want a full-time lodger? Then rent on a short-term basis  . If you live in the capital, renting a room out during the Olympics or other big events could bring in money. Grashpadder can advertise your space.
  Use your roof  
  You need the right kind of roof, but some energy companies pay the cost of fixing solar equipment (aroundPS14,000), and let you use the energy produced for nothing. In return, they get paid for unused energy fed back into the National Grid. However, you have to sign a 25-year agreement with the supplier  , which could prevent you from changing the roof.
question: If you want to use energy free, you have to   _  .
options: sign an agreement with the government pay around PS14,000 for the equipment sell the roof to some energy companies keep the roof unchanged for within 25 years